12 R. KIRK PATRICK. 



The autodermalia ( V. lc) are pentactins with or without a distal knob, with all the 

 rays (each 180 x 13/t in length) tapering and wholly spined. Hexactins occur, but rarely. 



The hypodermalia (V. Id-cF) (pleuralia and basalia) are oxypentactins with 

 rough or smooth rays, orthotropal or anorthotropal, the average length of a 

 paratangential being 1660 x 50/i. 



The autogastralia (V. le) are hexactius 266 x 12ju, and closely spined. 



The intermedia are holoxyhexasters (rare), hemioxyhexasters (V. If, f 1 ), and 

 abundant monoxyhexasters (V. If 2 , f 3 ), about 169/x, in diameter. The ealycocomes 

 (V. Ig, g 1 ) are 226/x, in diameter. The primary rays are only 8/u, in length ; the 

 capitulum is 14'5/A in length and 22/A in breadth; the secondary rays, 3 to 5 in 

 number, are thick, and either without any terminal knob, or with a very small one. 



Fig. Ih, a calycocome, with long primary rays, and without terminal disks, is only 

 87/A in diameter, and is probably immature. 



The discohexasters (V. Ik) are of large size, averaging 110/x. in diameter; the 

 primary rays (each 4'5/A in length) terminate in two to four long, disk-tipped 

 secondary rays. 



Fig. 11 shows a monodiscohexaster 120/A in diameter. 



The microdiscohexasters (V. 1m) are 5 I/A in diameter ; the primary rays, each 

 7/j. in length, terminate in a convex disk-shaped capitulum, from the distal surface of 

 which rays two lengths are given off, the longer rays having larger disks. 



Rossella podagrosa differs from R. antarctica in that the hypodermal oxypentactins 

 are without prickles ; secondly, the basalia resemble the pleuralia, whereas in R. 

 (iiifiirctica the basalia are anchor-like ; further, the ealycocomes of the new species have 

 very short primary rays ; and lastly, the buds are entirely different in the two species. 



Rossella nuda Topsent, has no velum. 



Rossella racomtzce Topsent, is likewise without a velum, and its surface is covered 

 with conules. 



Rossella hexactinophila, a new species about to be described, closely resembles 

 R. podagrosa, but is distinguished by its hexactin autodermalia, and by the different 

 shape and larger size of the ealycocomes ; also its oxyhexasters have more slender rays. 



All specimens were obtained from Winter Quarters by means of the D-uet. (1) No. 

 104, Hut Point, September 24, 1902, 26 m. (14 fathoms) ; (2) Nos. 118, 120, Hut Point, 

 November 13, 1902, 46m. (25 fathoms) ; (3) No. 137, Flagon Point, January 17, 1903, 

 18-36 m. (10-20 fathoms) ; (4) No. 139, January 23, 1903, 18-36 m. ; (5) No. 239, 12 

 hole, 46-55 m. (25-30 fathoms). 



ROSSELLA HEXACTINOPHILA. 

 (Plate III., fig. 4, and Plate VI., figs, la-g.) 



Sponge forming an elongated oval flattened sack with a sharp-edged oval orifice 

 provided with marginalia. With a velum ; and with a root-tuft about 2 cm. in length 

 mainly composed of oxypentactins resembling those of the velum. 



